Integrated 8-channel frequency measurement
The Siemens 6ES7312-5BD01-0AB0 CPU 312C packs 8 frequency measurement channels (FM) directly on the CPU — no separate counter module needed. That means you can capture encoder pulses, flowmeter signals, or speed feedback up to the CPU's cycle time without an extra slot in the rack. Onboard I/O totals 64 digital inputs and 32 digital outputs, enough to handle a small machine's sensor and actuator wiring without an expansion rack. The single-rack limit (max. 1 rack) keeps the footprint tight.
16 KB working memory, no MMC required
Working memory is 16 KB — enough for mid-size logic in LAD, FBD, STL, SCL, or GRAPH. The CPU does not require a Micro Memory Card (MMC) for operation; program and data reside in internal RAM with retentive areas that must be restarted at each restart. Programming is via STEP 7 V5.1 SP2 or higher. The CPU supports MPI (RS 485) for programming and peer-to-peer communication, and can act as an MPI client or server. For Ethernet or PtP, add a CP module — up to 4 CPs for LAN, 8 for PtP.
DIN-rail mount, 80 mm wide
The compact width leaves room alongside power supplies and I/O modules in a crowded panel. No backplane bus extension is possible (expandable: No), so all I/O must fit within the single rack. Plan your slot count accordingly.